The present invention concerns a gas dynamic compression wave machine of the type comprising a gas dynamic bucket wheel rotating centrally of a pair of lateral flanges at the air and the gas sides. The housing parts are equipped with inlet and outlet orifices, wherein the high pressure gas inlet orifice has a profiled configuration at its opening toward the bucket wheel.
For an understanding of the extremely complex gas dynamic compression wave process, which is not an object of the invention, the Swiss publication CH-T-123063 D is cited. The process sequence necessary for the understanding of the invention is specifically explained in FIG. 2 of the above-cited reference. The bucket belt of individual cells is defined by the unrolling of a cylindrical section of the standard bucket wheel, that moves during the rotation of the latter downward in the direction of the arrow. The shock wave processes take place inside the bucket wheel and effect essentially the formation of a gas-filled and an air-filled space. In the gas-filled space the exhaust gas is depressurized and subsequently escapes through the low pressure gas outlet. In the air-filled space, part of the suctioned-in fresh air is compressed and pushed into the high pressure conduit. The residual part of the fresh air is flushed by the bucket wheel into the low pressure gas outlet and thereby effects a complete exiting of the exhaust gases.
A shock wave machine of the above-described type is known from U.S. Pat. No. 3,074,622, for example, wherein the openings of the outlet conduits are profiled or rounded on the air side and the inlet openings on the lateral part on the gas side have a groove-like, i.e., a concave-polygonal, configuration. It is intended thereby to obtain a gradually increasing compression wave which is to yield a reduced reflection wave upon impact on the opening that is profiled on the air side, especially in the case of extreme mistuning in the lower rotating velocity range of the compression wave machine. Simultaneously, this configuration is expected to yield a reduced outflow at the high pressure inlet opening and a reduced inflow from the high pressure inlet. This is intended to correct the deviations of the wave transit time from the ideal transit time.
The present invention is intended to reduce the mixing of gas and air in the cells, a problem which cannot be solved by the measures disclosed in the above-discussed patents.